This invention relates to transmissions which use torque converters and planetary gearing and particularly those in which plural power paths are provided between the torque converters and the planetary gearing.
In transmissions of the type provided by the present invention, and in all transmissions, it is highly desirable to decrease weight and to increase strength and reliability while improving efficiency. While the achievement of any one of those goals may be more or less difficult, the achievement of all of the goals at the same time presents a complex problem, or, more appropriately many complex interrelated problems.
Creating high torque and high efficiencies, especially at low speed ranges, creates a special problem or group of problems.
The present invention seeks to advance solutions to those problems by providing transmission apparatus and methods of operation which accomplish the stated goals, uniquely using fewer parts. The unique use of fewer parts inherently advances solutions of weight reduction, improves strength, and reliability.
The present invention resides in the unique reduction of parts and in the unique interrelationship of parts to solve the problems and to approach the stated goals.